CHO-HuHTR2C cell line is clonally-derived from a CHO cell line, which has been transfected with a human 5-hydroxytryptamine (serotonin) receptor 2C, G protein-coupled HTR2C to allow expression of the human HTR2C. It is an example of a cell line transfected using our proprietary CBTGS gene screening and amplification system.

Background:

Serotonin (5-hydroxytryptamine, 5-HT) exerts its many physiological effects through 13 distinct receptor subtypes in humans. These subtypes fall into seven structurally-defined classes (5HT1 to 5HT7). 5HT2c receptors are expressed in brain and choroid plexus. This receptor has been used as a target for developing drugs to treat migraine and obesity.

1. Remove the packaging cell lines from liquid nitrogen and carry out a quick thaw. Float the cells in the 37°C water bath for 2 minutes until nearly (80%) thawed. Once cells are thawed, it is important to dilute the cells 1:10 in growth media immediately to reduce the potentially toxic effects of the DMSO preservative on the cells.2. Clean the outside of the vial with 70% ethanol before opening.3. Remove the cells from the vial and add slowly into a 15ml conical tube containing 10 ml pre-warmed media. 4. Centrifuge for 3 minutes 1000 xg to pellet cells and remove the supernatant.5. Add 14 ml of media and transfer cells to a T25 flask or a 100 mm culture dish.6. Place the cells in the 37°C incubator with 5% CO2.7. Allow incubation for 3-4 days to reach confluence. The cells will re-attach to the surface over a period of several days in culture at 37°C.

Subculturing:

1. Remove and discard culture medium.2. Briefly rinse the cell layer with 0.25% (w/v) Trypsin-0.53 mM EDTA solution to remove all traces of serum that contains trypsin inhibitor.3. Add 2.0 to 3.0 ml of Trypsin-EDTA solution to flask and observe cells under an inverted microscope until cell layer is dispersed (usually within 5 to 15 minutes).Note: To avoid clumping do not agitate the cells by hitting or shaking the flask while waiting for the cells to detach. Cells that are difficult to detach may be placed at 37°C to facilitate dispersal.4. Add 6.0 to 8.0 ml of complete growth medium and aspirate cells by gently pipetting.5. Add appropriate aliquots of the cell suspension to new culture vessels.Incubate cultures at 37°C.Subcultivation Ratio: A subcultivation ratio of 1:4 to 1:8 is recommended Medium Renewal: 2 to 3 times per week

Mycoplasma:

Mycoplasma Status: Negative (MycoAlert Kit)

Freeze Medium:

Complete growth medium 95%; DMSO, 5%

Storage:

Liquid nitrogen

Preservation:

1. Detach cells from culture dish according to the Sub-Culture Procedure.2. Resuspend cells at a density of 5 x 10^6 cells/mL in freeze medium.Note: A T-75 culture flask typically yields enough cells for preparing two frozen vials.3. Aliquot 1 mL cells into cryogenic vials.4. Place vials in a freezing container and store at –80 °C overnight.5. Transfer vials to liquid nitrogen for long term storage. If properly stored, cells should remain stable for years.

Safety Considerations:

The following safety precautions should be observed.1. Use pipette aids to prevent ingestion and keep aerosols down to a minimum.2. No eating, drinking or smoking while handling the stable line.3. Wash hands after handling the stable line and before leaving the lab.4. Decontaminate work surface with disinfectant or 70% ethanol before and after working with stable cells.5. All waste should be considered hazardous.6. Dispose of all liquid waste after each experiment and treat with bleach.